Method for manufacturing gases



Jan. 5,

H. J. cARsoN METHOD FOR MANUFACTURING GASES Filed Oct. 31. 1930 vio Patented Jan. 5, `A1937- UNiTEo STATES amsn mamon son. MANUFACTURING casas nii-am J, cama, cesar Rapids, nin Application october 31,1930, sei-iai No. 49am claims (ci. is-zw V ftions described and@ claimed in my co-pending buretted water g'as having a relatively high heat- `ing value.

applications 199,572, med June 17,1927, and 353,576, filed April y28, 1929, comprehends:

Improved methods of z furnishing preheated air 4 for blasting; generating and superheating steam for gas making; air blasting a generator fuel bed; admitting steam to a generator fuel bed; removing of ash and clinker forming material from a water gas generator in liquid form; introducing iluxing material into a generator fuel bed; gasifying bituminous fuel in a water gas generator;

` recovering 'liquid hydrocarbons and ammonia4 l from bituminous fuel; introducing-and gasifying liquid hydrocarbons in a carburettingchamber; superheating and/or decomposing methane and/or natural and/or other gases for producing of hydrogen; theV production of gases high in hydrogen content from non-volatile and/'orbituminous fuel ancl/orhydrocarbons including butane and propane; and the vmanufacture of car-V As is well known, in the usual operation of water gas sets, the time-is roughly divided into two periods; the blasting or heating up period, and the 4running or gas-making period. 'I'he heat developed lduring lthe air blasting period and stored in the generator fuel bed,is available in the gas making period for decomposing the steam admitted to the generator. In the' usual operation of carburetted water gas sets the potential and sensible-heat in the blow gases leaving the generator is used 4to store heat in regenerative chambersknown as carburetting and gas superheating chambers, the heat so stored being used for vapori'zing and cracking liquid hydrocarbons and fixing the resulting hydrocarbon gases during the gas making period.

The air for blasting usually. enters the generator at about' atmospheric temperature and the steam for gas making usually enters the generae tor with a relatively small amount of superheat, if any, and often containing moisture.v The air .must be heated in the` generator to ignition temperature before combustion takes place and any moisture-in the steam must be vaporizedand the steam heated to a reaction temperature of over 1800? F. or more for steam decomposition before water gas is formed in any appreciable amount. 'I'he blow gases,- from air blasting, leave the apparatus while containing a substantial amount of sensible heat in addition to the potential. heat in any combustible gases therein.

In practice,v at the beginning of a running period, the decomposition of steam is rapid and .nearly complete for a short period, but falls oil. rapidly thereafter, owing to the lower rate of decomposition as the generator fuel bed temperature falls. g

Very little steam is decomposed at temperatures below' 1832 F. whereas the rate of decomposition is estimated to double with every rise of F. in temperature above that point and such decomposition is very rapid at temperatures of 2192 F. and higher. While the temperatures in the steam decomposition zone in a generator fuel bed' may vary at different levels in that zone, the minimum practical temperature of its highest iol temperature portion. which should be of suncient thickness to give the steam enough time of contact with the hot'fuel to` form blue water gas in practicable amounts, is about 1832" F. and'the heat in the fuel bed useful for steam decomposition is the heat stored above that temperature.

Heretofore, insumcient account has been taken of the foregoing facts. Steam admitted to the generator is actively decomposed at first, but

decomposition is soon arrested as the fuel temperature is 'lowered by the cooling action of such steam decomposition. As the temperature' drops. less and 4less of the steam admitted is decomposed, and the resulting' increasing excess of undecomposed steam has the harmful effect of further cooling the fuel bed with no useful result vTo restore heat. tprage to the fuel bed at proper temperature leve 'iafter such cooling: fuel, air,

and time are necessary, and as the fuel bed must be heated first to the temperature where steam decomposition begins at an eifective rate and as the useful heat storage isthat above about l832 F. the blasting and heating to bring the fuel temperature in the steam decomposing zone up This invention contemplates theuse ofotherwise. waste heat in thef combustible gases and blast gases to superheat the steam and preheat,v

the air to the generator, thereby conserving the heat stored and generated thereinat high temperature levels for the directly usefulpurpose of steam decomposition and gas formation, and

permitting operation` at higher average terni-i4 peratures in the generator. l In air blasting a generator fuel bed it is well known that more and more carbon monoxide is produced for a given rate of blasting as theY temperature of the fuel rises and the high temperature zone in the fuel increases in thickness.

It is also well known that the percentage of carbon monoxide in blow gases may be limited by increasing the rate of blasting, thus reducing the time of contact of the burned gases with the hot fuel. o

In the usual method of air blasting water gas sets the air is blown into the bottom of the generator through grates and the entire fuel bed to the blow gas ofltake. The carbon monoxide content of the blow gases is limited by shortening the air blasting and gas making periods as much as practicable and air blasting at the highest practicable rate. Less heat is stored in the fuel in the shorter blasting period and less is needed for the short gas making period, and less carbon monoxide is produced in the blow gases.

Optimum conditions for the decomposition of steam and run gas formation require the longest practicable time of contact of the steam with the fuel' at the highest practicable temperature. A thick high temperature fuel bed is desired.y

This invention contemplates the maintenance of the CO content of the blowfgases within the desired limits and the building up of a steam decomposition zone of greater thickness and maintained at a higher temperature than is practicable in the usual methods of operation now used. l

This invention contemplates the introduction of air to the fuel bed at different levels separately controllable at each level so as to limit the time of contact of the burned gases with the high temperature fuel resulting from combustion 4tinued as a h igh temperature zone is built up near that level. Air may then be introduced at the next higher level so as to by-pass the hot layer of fuel resulting from blasting at the rst level, then discontinued at the second level, and commenced at the third level and so on until a high temperature fuel bed of the desired thickness is built up.

'I'his invention accordingly contemplates the admission of air at one level at a time or at differentY levels simultaneously. When air is continuously admitted at one level the carbon monoxide in the resultant gases may be burned by air simultaneously admitted at another level thus decreasing the carbon monoxide contentt of the blow gases:

The rate of air blasting is limited by the point at which excessive amounts of fuel are blown out of the generator. In present operation with the air for blasting admitted under the generator grates and the fuel column not uniformly porous, the air seeks the path of least resistance through the fuel and channeling results with overheating of some portions of the fuel bed and little heating of other portions.-A As a result a. substantial part of the fuel bed is relatively inactive.

This invention contemplates that air for blasting will be supplied to the generator at relatively high velocities through a plurality of tuyres in the-generator at. different levels as desired thus insuring a relatively uniform air supply to, and

' penetration of, the generator fuel bed.

In present operation the steam for gas making follows the path of least resistance through the fuel bed and often with a channeling effect.

-This invention contemplates the admission of steam to the generator at relatively `high velocities through tuyres in the generatorv at dierent levels as desired, thus insuring the admission of steam uniformly to the different points of the fuel bed. 4

In present operation the steam and air enter the base of the generator relatively cold and chill the bottom zone of the fuel bed. vDown steam runs are necessary from time to time to drive the heat down toward the grate as otherwise the cold zone would gradually move upwardly.

This invention contemplates that with steam superheated above `the ignition temperature of the fuel and/or admitted above the bottom zone and with or without preheated air, the bottom zone of fuel is kept sufficiently hot so only up steam runs need be made.

This invention also contemplates the making of down steam runs and a combination of up and down steam runs and a practically complete recovery of all the otherwise waste heat in the usual water gas process as well as reducing the number of or avoiding the use of valves in hot locations.

In present practice, gas making is continued until the accumulation of ash and clinker in the lower portion of the generator fuel bed prevents further operation in a practicable manner. Gas making is then discontinued, to permit the removal of ash and clinker, after which operations may be resumed. 'I'his invention'contemplates the easy removal of ash and clinker in th form' of molten slag so as to permit continuous or nearly continuous operation with a uniformly clean fuel bed and without the arduous labor and loss of time usual in present operation or the use and maintenance of c ostly mechanical grates for continuous ash and clinker removal.

This invention furthe'r contemplates that air and steam may be admitted selectively as desired and gas drawn olf so the liquid slag formed in the bottom zone'of the generator fuel column will not be substantially exposed to the cooling action of the entering steam, will remain hot during the period of steam admission, thus permitting ready ignition at the beginning of the blasting period and keeping the slag subi contemplates passing part or all ofthe blue water y i 2,066,670 steam superheated near to or above the fusing tion.

'I'he use of preheated air for blasting facilitates the slagging operation. A flux may be charged with the fuel or introduced in the bottom zone of the fuel bed or blown in admixed with the blasting air as needed and desired. In the latter case the flux may be immediately used inliquifying the slag and the time interval required for fiuxing `material charged with ,the fuel to work down to the slagging level is avoided.

This invention contemplates the introduction of a fiuxing material in the bottom zone of the fuel bed when desired, also the introduction of combustible gas with the blasting air in the bottom zone in case of diiiiculty in slagging which may, for example, be occasioned by a deficiency of combustible in the fuel at the slagging level. The'blasting air may also be enriched with oxygen for further hastening combustion and liquifying the slag. A limited amountof air and/or oxygen may be admitted at the lower level during the gaslmaking -period to keep the slag liquifled.

When bituminous fuel is used 'in agenerator ofI the usual type having the blue and blow gas ontakes at the same level, volatile matter from the fuel is driven off during the gas making period and also during the air blasting period. Also, in the usual up and down run'method of operation in which steam for gas making is alternately admitted above and below the fuel bed, the hydrocarbons distilled from the fuel during the down run lportion are passed throughthe hot zone of the generator fuel bed and broken down through the fuel in the upper zone for devolatillz' ing the fuel and any remaining portion of the blue vgas, drawn off separately as for enrichment with liquid hydro-carbons. With fuel containing littlev or 'no volatile matter, such as coke, the invention i such fuel before it descends into the lower water gas generating zone.

'I'his invention also provides for a carbonizing zone-above the generating zone with the heat in 'l the blue gas and/or superheated steam admixed' with air or oxygen when desired and utilized in internally heating and carbonizing the fuel.

In c arbonizing fuel in water gas generators by internal and/or external heating, -as -above described, diiiiculties are experienced with some fuels which -on heating swell, arch or hang in generators and form a plastic zone through which gases are passed with diiiiculty, if. at all.

The volatile matter of bituminous fuels is of varying composition and distillable at different temperatures. The volume and quality of the volatile matter given off varies with the temperature and time of heating. l

When they volatile matter distilled oif at relatively higher temperatures passes through cooler 5 fuel, some or all of it is usually condensed on the cooler fuel. This condensate encases the lumps or particles of fuel in a'liquid envelope often of a plastic nature which is not again vaporized until the fuel passes into a zone of higher t'eml0v perature. Meanwhile the coal lumps and particles contain volatile matter distillable at relaltively low temperatures, which being partially or wholly confined within the liquid envelope, causes the fuel to swell.

If the volatile matter evolved from bituminous fuel as it is heated is removed from contact therewith substantially as it is formed under temperaturel and partial `pressure conditions above the condensation'point, the time required for distill- 20 ing off lthe volatile matter at any given temperature-is greatly reduced; cracking of the hydrocarbons so evolved is avoided and the condensable portion of these hydrocarbons may be recovered in liquid form. With the hydrocarbons drawn off 25 as formed and cracking avoided, the heat required for carbonization is substantially less.

If swelling or sticking coals are preheated for a time at 900 F. more or less, the swelling properties and tendency t'oward the formation of a plastic zone is thereby reduced. A

This invention contemplates when desired the devolatilization of the fuel by the heat in the blue gas and any. undecomposed steam mixed therewith passing through it at relatively higher temperatures lthan are obtained in usual practice and supplemented by other methods more fully hereinafter described.

This invention also contemplates preheating the coal to prevent sticking and the formation of a plastic zone'andthe distillation of the fuel under controllable temperature conditions to permit the evolving and recovery of condensible hydrocarbons of varying qualities as desired as hereinafter more fully described.

The invention also contemplates the distilling 0f the newly charged bituminous fuel and production of gas high in hydrogen content with steam preferably highlyV superheated, passing downwardly through it and thence with the hydrocar- 50 -bons distilled from the fuel on vdownwardly through incandescent fuel to thereby crack the hydrocarbons mostly into hydrogen and carbon and/or water gas from the steam and the carbon thelreby `liberated and/or the carbon from the fue v This invention further contemplates the production of a high hydrogen content gas as by liquid hydrocarbons sprayed in the upper part of the generator ina downward current of highly superheated steam with the mixture passed downwardly through the incandescent fuel.

In the manufacture of` carburetted water gas from bituminous fuel, the invention contemplates passing a part of the water gas through the carbonizing chamber and the remaining portion in desired volume through a carburetting chamber for enrichment therein by hydrocarbon vapors from liquid hydrocarbons.

` With coke used as fuel the proportions of wa- 'ru ter gas drawn off separately, passed through newly charged fuel and through the carburetter or through regenerators for superheating steam and any air or oxygen admixed therewith may be varied as desiredl and as hereinafter described.v

The invention also contemplates the admission of steam in the lower zone of the carbonizing chamber for the formation of ammonia and/or 4blue gaswith such formation furthered, when desired,`by"the presence of lime or limestone when In the manufacture of carburetted water gas it .t

is well known that optimum conditions for the gasification or cracking of liquid hydrocarbons -in the carburetter require the maintenance of temperatures within fairly narrow limits. It is also wellknown that in present operation the temperatures in the carburetter fluctuate widely, with a fairly rapid deterioration of the heat t absorbing material, usually fire brick, because of the thermal shock incident to the temperature fluctuations. 'Ihe temperatures in the top courses of checker brick have been found to uctuate from an average minimum of 640 F. to an average maximum of 1886 F. with extreme'meanvariations from 513 F. to 2000 F. Shut downs and replacements of checker brick are frequently necessary. At the higher temperatures the hydrocarbons are over-cracked with a deposit of carbon and the formation of objectionable compounds such as naphthalene and, at the lower temperatures, the hydrocarbons are not completely cracked or utilized and other objectionable compounds such as indene and styrene are formed.

The brick in the carburetter are rapidly cooled by the vaporization and cracking of the hydro- .carbons and in the usual up and down run methods of operation, of carburetted water gas sets are further cooled by the relatively cool blue gas and undecomposed steam which enter the carburetter at temperatures substantially lower than required for optimum hydrocarbon cracking conditions. This cooling often progresses to such an extent that it is difiicult to ignite the blow gases and secondary air during the following air blasting period.v I

The invention contemplates the use of a combustion and heat absorbing chamber between the generating and carburetting chambers in which heat may be stored during the blasting period for preheating the blue gas and undecomposed steam toward and above the optimum temperatures for the gasification of the hydrocarbons before vsuch blue gas and undecomposed steam enter the hydrocarbon admission zone.

During the gas making period the water gas and undecomposed steam are heated to relatively high temperatures in passing through the heat absorbing chamber and in entering the hydrocarbon gasification zone carry heat to the hydrocarbon particles in this chamber with more nearly uniform and optimum temperatures prevailing in the gasification zone.

'I'his invention also contemplates drawing off the blue gas from the generator at a sufficiently high temperature fr furnishing the heat for cracking and gasifying the hydrocarbons within the desired temperature limits and the use of a mixing chamber in the hydrocarbon admission zone in the carburetter to allow for the mixing therein of the highly heated entering blue gas and steam with the hydrocarbon mist or particles directed into andagainst the descendingK gas stream'. The mixture of this entering hot gas and steam with the heat radiated to these particles from the carburette lining and adjacent refractory material bring the hydrocarbon particles to or nearly to optimum temperatures for cracking. In the presence of a reactive gas such as hydrogen in the blue gas at optimum cracking temperatures, stable hydrocarbon gases are formed and a practically complete conversion of the carbon and hydrogen in the hydrocarbons into such gases is effected.

A uniform or nearly uniform mixture of hydrocarbon particles or gas and blue gas and steam from the generator will take place inthe hydrocarbon admission zone, for the hot .gas and steam after passingthrough the supplementary heat absorbing chamber and in striking the hydrocarbon particles, cool and drop out of the way of the hydrocarbons and gas and steam introduced thereafter, with the uniform descent of the mixed gas column in the chamber. The amount .of secondary combustion and heat stordescent of the age in the heat absorbing zone may be so regulated that the blue gas and steam will be heated to the required temperature in conjunction with heat radiated to the 'hydrocarbon mist and blue gas-hydrocarbon mixture from adjacent refractory surfacesfor producing optimum temperature conditions for hydrocarbon cracking when cooled by and mixed with the hydrocarbon particles.

The mixture of blue gas and hydrocarbon gas and steam and any hydrocarbon mist therein may, when desired, then be passed through heat absorbing material, such as checker brick, which have not been exposed to the ames of the seconda-ry combustion of the blow gases and have temperatures substantially within the optimum temperature range for hydrocarbon gasification so that the hydrocarbon mist is then cracked therein.

The relatively large volume of blue gas entering the carburetter provides low partial pressure conditions for the hydrocarbon vapors which furthers the conversion of liquid hydrocarbons into stable hydrocarbon gases. Reduced absolute pressures further favor the conversion of the liquid hydrocarbon into stable hydrocarbon gases. When it is desired to reduce the. absolute pressures, the carburetter gas outlet is equipped with a vacuum pump which may be sufficiently large to handle al1 blue and hydrocarbon gases. The pump in such case is preferably arranged to draw the gases through a condenser so as to reduce the gas volume and the size of pump required. Any outlet from the generator other than the carburetteroutlet may also be provided with a vacuum pump and condenser.

The relative proportions of gas drawn off through each oiftake may be regulated by the.

size and speed of each pump.

The volume of gas withdrawn through each outlet may also be regulated by dispensing with the pump in the second gas outlet and providing a previously described into lighter hydrocarbons of 7 showing a modified form of the lower part of the the desired density and heating value at temperatures below those at which naphthalene is formed and above those temperatures at which indene and styrene are formed.

When it is desired to produce a gas highlin hydrogen from methane and/or naturalfg/as, the

invention contemplates the use of methane or natural gas'with steam in the foregoing.

The invention contemplates a process wherein regenerative chambers'are utilized in which heat from the blow. and/or run gases is stored and used for superheating and/or generating steam and preheating air, and so designed that the blast gases pass downwardly and the steam and air pass upwardly through the heat absorbing material in these chambers. A practically complete utilization of the capacity of these chambers is thereby effected.

Thedecompositionof methane and/or natural gas and like hydrocarbons into carbon and hydrogen in practicable amounts requires an appreciable time of contact at high temperatures. l'I'he `s uperlxeating of the methane and/or natural gas j and building up of a thick high temperature zone in the fuel bed byair blasting as previously described provides optimum conditions for the production of hydrogen from these gases.

The methane, natural or other gas such as reflnery gas is admitted to regenerators heated as previously described for steam in water gas production, the air blasting methods being the same -as previously described, and after being superheated in such regenerators is passed to and through an incandescent fuel bed in the generator where the carbon is mostly deposited, and

the hydrogen and any gases admixed'therewith is drawn off as described for-water gas.

In the preceding, I have outlined briefly certain features and disadvantages of water gas generation as heretofore commonly practiced and the objects of the present invention.

Qther objectsA of my invention will more clearly appear from the description andclaims hereinafter following.

In the drawing forming a part of this specication, I have illustrated suitable apparatus, with certain indicated modifications under different conditions, which may be employed in the practical carrying out of my improvements in water gas generation. In said drawing- Fig. 1 shows a carburetted water gas plant partly in elevation and partly in vertical section, suitable for carrying out my improvements and in which the operation may be varied and differi ent parts omitted when desired. i

-- generator in Fig. 1.

Eig. 4 is a fragmentary sedion in elevation showing another modified form of the lower part of the generator in Fig. 1. v

The apparatus shown inFig. 1 is adapterlmfogm.V the manufacture of carburetted orbluewar gas from bituminous fuel or non-volatile fuel, such crackng methane and/or natural or'other hydrocarbon gases as herein described. The apparatus will iirst be described for combnatio up and down steam runs for thepmanu- .water gas generating zone and containing'inainly vdesired and hereinafter described. I

4assembly and fuel. i

facturepf/carburetted watergas from bituminousl fuel.

In Fig. 1 a gas generator I0 is shown communieating with a carburetter II which communicates with a regenerative chamber I2. 'Ihe chamber I2 isa steam superheater in which heat from the blast gases is stored for superheating' steam.

The steam superheater I2 communicates with an air preheating chamber I4 here shown as a recuperator which may be of the double regenerator type when desired in which the air for blasting is preheated by the hot products of combustion simultaneously passing through it.`

A regenerative chamber is also shown at I5 which is adapted ,mainly for superheating and/or generating the uprun steam by the 'sensible heat in the downrun gas, and also for carburetting the down-run gas when desired.

A condenser or waste heat boiler is indicated at I6 through which combustible gas from carburetter II may be drawn off and cooled before enteringa vacuum pump as Il, or passed to such other apparatus as desired.

A blower for supplying the blasting air through 25 inlet 54 to the preheater I4 or through by-pass 53 to air header 58 is indicated at I8. A' seal separator through which the down-run gas may be withdrawn from chamber I5 is indicated at I9. When desired the connection I9 may com- 30 municatewith a condenser orwaste heat boiler and/or vacuum pump in the Same manner as I Ii and I'I are connected to chamber II.

As described hereinafter the regenerator I5 is used when down steam runs or combination up 35 and down steam runs are made and is dispensed with when up steam runs only are made.

'I'he generator 'In' is. shown in section having mainly two zones, `the'lower/"zone 20.. being the incandescent fuel. The upper zone contains a carbonizing chamber 2I which is. charged with fuel, such as bituminous coal, 'and an ash fiuxing material. such as limestone when desired, through any suitable charging device as 22. Air blast inlet' means are provided at different levels as at 23, 23a, 23h, and 23e. vSteam inlet means are shown at 24 or24a, 2lb, 24e, 24d, or at 30 as 'Ihe carbonizing chamber is shown with an annular passage around it for the passage of air blast gases from the lower zone to an offtake 3l.-

The carbonizing chamber, when bituminous fuel such as coal is used, preferably contains an assembly 33- made. of a series of "cylinder or cone units of any desired form with the bottom end of each unit projecting overand below the top of the next lower cylinder to prevent fuel falling therein andto provide openings for the upward Vescape of volatile. matter from the fuel into the open passage through the units as will be understood A cap 34 is adjustable as by a cable 35 to regulate the division ofilow of gases through the A valved offtake 36 is shown leading from the carbon'izing chamber.

The generator vis shown having a hearth 3l, preferablyl sloping tofacilitate the drawing o3 'of .liquid 'slag as through discharge pipe 32. A 70 ux feed opening, closable in any suitable manneiiisin'dicated at 10.

Down run gas leaves the generator through either of two. passages, as indicated at 28 which is located above. the hearth or through $0 at the 75 -level of the hearth. One or the other of these passages is dispensed with as desired. When the down run gas oitake passage is also used for admitting steam to the generator the valve as 28 or 30 may be dispensed with but a valve is used when steam is forced' through tuyres to generator as at level 24.

The hot down-run gas stores heat in the regenerator I5, and in its passage therethrough may be carburetted by hydrocarbons admitted as at 10 with the resultant carburetted gas drawn oil as through oitake I9 and seal separator I9.

The stack 14, closable by a stack valve 15, is an outlet for any air blast gases used for heating the regenerator which may be burned therein by air admitted at 13.A

The heat stored in the regenerator I5 during the down steam run in the generator is used for superheating up run steam admitted as through 1I and any air admixed therewith admitted as through 12 when combination up and down runs are used.

Water and/or works effluent may be sprayed into the regenerator as at 10 and vaporized in the rising column of superheated steam from that admitted at 1I and superheated before admission to the generator when the cycle of per therewith from the regenerator I5 to the carbonizing chamber at 24h to blanket out the air blast gases during the air blasting period when desired and to act as a vehicle and a heating agent for removing distillation vapors and gases given off meanwhile.

The valve 31 in the passageway 31 to the carburetter may be dispensed with as hereinafter described.

The carburetter Il has a combustion chamber 38 for burning air blast gases from the generator by air admitted through 39 to heat the heat absorbing material 48 to a relatively high tem perature; 'I'he usual point of admission of hydrocarbons is indicated at 42 but the invention contemplates the introduction of hydrocarbons after the zone of highly heated material as in 43 where the hydrocarbons are injected into and against the descending gas stream through the horizontally disposed inlets 44, as shown in Figure l. Heat absorbing material as 4I of suitable size may also be provided when desired to -vaporize and/or crack any uncracked hydrocarbons in the gases passing therethrough.

- In making carburetted water gas with combination up and down runs, the steam superheating chamber l2 may be dispensed with and the air preheater I4 and passageway 50 connected directly to the blow gas outlet passage 45 of the carburetter.

. Under such condition, the blow gases, after passing through zone 4I lenter space 6I, pass through opening 62 into passage 45 thence through passage 50, air preheater I4, stack 5I and valve 52 to the atmosphere, the air for blasting simultaneously passing through I4 andy being preheated thereby.

The up run gas in passing through the pre-v aecomo heating chamber 48 is highly heated thereby and carries heat for cracking the hydrocarbons introduced at 44. The carburetted gas then passes on through the chamber 4I into the checkerwork 4Ia and stores heat therein and is withdrawn through 51 and 58.

When desired the regenerative portion 4I a may be in a'separate chamber with a suitable passage to it from 51, as for example, being installed in offtake 58.

The down run steam and any air admixed therewith is admitted through 65' and 66 respectively and passing through 4Ia is superheated by the heat previously stored therein by the outgoing carburetted gas as above described, and in passing thence through 4I and 40 is progressively more highly superheated before passing to the generator.

When the regenerative portion 4Ia is omitted the steam and any air admixed therewith may be admittedin the passage 45 as at 65" and 88" with the portion 4I when used and passage 45 extended downwardly to space 51.

The operation for making carburetted water gas with up and down steam runs is carried on as follows: .l

With valve 31' open and chamber I2 and valve 46" omitted and carburetter outlet 48 connected into air preheater. inlet 50 and-stack valve 52 open and all other valves closed, a ilre is kindledl on the hearth 3l and the generator charged with fuel, preferably coke, through charging door 22. Air is admitted from supply pump I8; through 54 and I4; thence through 55, 56; lines 25 and then through tuyres 23' to the generator at level 23. As blasting is continued at this level'and the fuel adjacent thereto is heated to a high temperature, the carbon monoxide content of the combustion gases increases and is burned in combustion chamber 38 of the carburetter by air admitted through 39. The heat absorbing material 40 is heated to a high temperature and the gases passing through 4I heat it also and pass thence through 6I and 62 and passageways 45, 46, and 58 I to the air preheater I4, preheating the blasting air simultaneously passing therethrough and thence out through stack 5I and stack valve 52.

As the carburetter is heated to the desired temperature and carbon monoxide in the blow4 gases increases in volume, air is admitted at a higher level as 23a, to burn part or all of the carbon monoxide so produced, with the admission of air at 39 continued in sumcient volume to burn any remaining carbon monoxide in the blow gases.

Also as the fuel adjacent to level 23a becomes so hot that carbon monoxide is produced in greater volume than desired, air blasting is discontinued at level 23a and resumed at level 2lb until a fuel bed of the desired temperature andA thickness is built up and the carburetter is heated to the required temperature.

In air blasting the fuel bed, air may be admitted as before, first at level 23. and then discontinued as the fuel adjacent thereto becomes sui'ciently hot, and resumed and discontinued at level 23a in like manner, also at level 2lb until the fuel is suiliciently hot'. It is, however, preferable to continuously air blast the fuel at the lowest level thereby making the lowest section of fuel a carbon monoxide generator and then burning the carbon monoxide so produced by air 'I'he lower portion of the fuel bed during blasting becomes intensely hot and any ash or clnker forming material therein is liquiiied.

Air may also be admitted at 23e at or near the top ofthe fuel in the generating zone to burn the blow gasesk and give additional external heat for the chamber 2|.

Also during the heating up period, a portion or all of the blast gases for part of the period mayV i u; of combustion passing out through stack.'|4 and stack valve 15. Meanwhile the valve 31' or 48' or 52 may be closed to force all blow gases ,into

" the regenerator l5 when that is desired and when only aportion of these blow gases is passed therein the valves 15 orv 30 or 28 and 31 or 46' or'52 are so regulated as to effect the required division of ow through I5 and the other apparatus and out through stack valves 15 and 52. This is preferably done instarting up the apparatus to give the regenerator its initial heat and to then purge the regenerator of air but m'ay be done thereafter if desired.

When the heat in the down run gases lis relied on to heat the regenerator I5, the stack 14 andA valve 15 may be dispensed with and a short purge run first made by passing steam through the re" Asteam is admitted at 1i and admlxed with a restricted amount of air and/or oxygen when desired through. 12. The mixture passes through the heat absorbing material, is highly superheated thereby and passes thence to the generator fuel column" through 28. (the valve 28"and passageway ,H30 and valve 30' being omitted) and then through 24d' to'thevfuel at level 24a. When, however, the l openings at level 24a are too large to admit the steam to the fuel at the` desired velocity, the valve 28' is used and closed and the steam is passed throughv21 into the fuel at level 24.

In either instance the steam bypasses the lower hot section of the generator thereby avoiding or reducing the cooling action of the steam and its decomposition on the underlying fuel and slag.

'Ihe superheated steam in contact with the hot fuel is decomposed into hydrogen and carbon monoxide mostly and passes up through the fuel and around the carbonizing chamber 2| through 31, 38, and ls additionally heated in 40. In entering 43, liquid hydrocarbons ,are sprayedinto the descending gas stream through.44. The highly heated blue gas with the radiant heat from adjacent refractory material heats the hydrocarbon When it is desired to carburet the' gas 'under lower absolute pressures, a vacuum pump I1 is provided with' which the regenerator 5, generator I0, andcarburetter may beoperated'at substantially lower pressures. This 'reduced relatively low point.

'being controlled to secure the desired cracking pressure may be-used in the carburetter only with the valve 31' used to restrict the ow from the generator to the carburetter.

When the up runhas continued for a sufficient time, the steam inlet 1| and air inlet 12, when used, are closed and the necessary closure made in the outlet 58, Steam is then'admitted through 65 and admixed with air as desired through 88 and passes upwardly through 4|a, 4|, 43, 40, receiving a preliminary superheat in 4|a by the heat stored therein by the outgoing oarburetted gas and a final high temperature superheat in 40. It passes thence to the generator and through the fuel in 28 and ismostly decomposed therein and out as at level 24a and passageway 28 to the regenerator I5 and the gas passing therethrough gives up most of its heat therein' and passes out through I9' and I9 to such other apparatus as desired.

'I'his down run gas leaves the fuel bed at a relatively high temperature and when desired may be carburetted by hydrocarbons sprayed in as at 10 or 10. the heat in the gas being relied on to furnish the heat for cracking and gasifying the hydrocarbons. In this case, the heat'fin the gas may be intensified by heat stored in the regenerator by the combustion of blow gases in the regenerator as previously described. It is, however, preferable to use enough' down run steam sov the down run gas will give oil the required amount of heat in regenerator I5 to superheat the up run steam to the desired temperature and at the same time reduce the temperature of theoutgoing downI run gas through I9' and I9 to a Whe .'1, however, the vheat in Ithe down run gas is more than sufficient for superheating the up run steam, this gas may be carburetted` with hydroarbo'ns admitted at 10 as previously stat-ed or 10- or some of the up run steam may be gen'- erated by water or works Vefliuent sprayed in as at 10, in which case the steam admitted at 1| is superheated and striking the waterI mist introduced at 10 vaporizes it, and it all passes upward and is superheated before entering the generator: Water or works eiliuent may be similarly vaporized in the carburetter during down runs through admission means as at 44 in a rising. column of super-heated steam.

The heavier hydrocarbons suchas butane and propane may be introduced in the carburetter at 44 and in regenerator I5 at 18 when desired, the temperatures of the blue gas passing there# through and refractory surfaces adjacent thereto of thesehydrocarbons with an avoidance of naphthalene. and indene and styrene and other objectionable compounds as previously described.- Op,'

i timum temperature conditions for the breaking down of these hydrocarbons and absorption of hydrogen from the blue gas for the formation ofl methane and/or other hydrocarbon gases in the maximum practicable quantities is thereby' ob-` tained.- The production of the latter is of par` cti'cular value for augmenting a natural gas supply desired manner. The valve 38" may be omitted f when 30 is used to admit the up run steam which may be do'ne when the hearth 3| is relativelyv '75 free of liquid slag and the steam is highly superheated. It is however preferable with 30 used, to use the valve 30' closed during the up run period and force the steam through 21 at level 24 to prevent any chilling action on the lower section of fuel and any liquid slag therein or on the hearth.

I'he operation with up and down runs and air blasting at different levels as desired is continued substantially as previously described. During the run or gas making period the up and down run portions may be varied as desired.

As the operation progresses the fuel column is replenished as desired through charging inlet 22 with coke or bituminous fuel. With coke used, the assembly 33 may be omitted, also the chamber 2I and inlet and connections therefor at level 24h, and the generator filled with fuel to any desired height with air blast levels suitably disposed throughout the height thereof.

Also, with coke used, the upper portion of the generator may be as shown in Fig. 2 with the blast gases drawn off through 6I and 82 with Aor with-` out a valve therein as previously described, the passage 82 connectingl into the carburetter II. In this case with assembly 33 omitted and newly charged fuel in the upper portion 80, part or all of the up run blue gas may be taken as desired through this fuel and oif through offtake 36, the sensible heat thereof being used in preheating the newly charged fuel.

.With bituminous fuel used, the chambers 2| in Fig. 1 and 80 in Fig. 2 are used as carbonizing chambers. In Fig. 1, the chamber is heated by the blow 'and run gases passing around it, the run gas that is passed through it and the superheated steam admixed with air admitted through 24h when desired as during the air 'blasting period admitted at 2lb. The blue gas in passing up through 2l sweeps the volatile matter from the fuel, .enters the assembly at the bottom and passing the annular openings throughout its height, brings in and induces into the assembly the vapors and gases from the fuel at a temperature close to theirv distillation temperature and under partial pressure conditions such that these pass through the assembly and out through 36 without condensation. A rapid rate of carbonization is thereby obtained and ythe tendency of the fuel to swell and form a plastic zone is thereby reduced or avoided.

Carbonization is similarly effected in 80 in Fig. 2 except that the heat in the blue gas passing therethrough and/or steam and combustion of any air or oxygen admixed therewith is relied on to supply the heat for carbonization.

The fueltemperature inthe chamber 2| with steam admitted at 24h may ,be so controlled as to provide optimum conditions for the formation of y ammonia whichy is drawn off withthe gases through offtake 36.

In making blue gas with up and down runs, the carburette'r II is omitted and outlet 31, valve 31 being omitted, is directly connected into 46,

the valve 46 being also omitted as well as theH superheated steam line 61, valve 68 and line 26.

In this case the steam superheaterIZ is heated bythe blow gases and the secondary combustion lthereof by air admitted through 48.

The steam admitted therein at 65 with any air or oxygen admixed therewiththrough 66 is superheated and passes tothe generator as before and the blue gas formed therefrom passes to the regenerator I5 as before.

The up run steam is admitted to regenerator I5 as before and the blue gas is passed through the newly charged fuel as 2|Ifin Fig. l or 80 in Fig. 2, and out through offtake 36 with the sensible heat thereof utilized in preheating and/or distilling the fuel therein as previously described.

In this case the sensible heat in the down run sage 31 connected directly into 46 with valves 31 and 46 and piping 61, Bil'and 26 omitted as previously described for making blue gas. The upsteam connections to the' generator are also omitted. In this case the steam passes from the superheater I2 as before for blue gas and the down run gas is carburetted in I5 by hydrocarbons admitted at 10 or 10', the sensible heat in the gas being relied on to crack and gasify the hydrocarbons. The resulting gases are drawn off through I9 and seal separator I9 or waste heat boiler or condenser such as shown at I 6 equipped with a. vacuum pump I1 for lowering the absolute pressures during the carburetting process as previously described.

With bituminous fuel used in this case, superheated steam and air or oxygen admixed therewith as desired may be passed up through the carbonizing chamber for carbonizing and carrying off vapors and gases as previouslydescribed.

With up runs only used, the regenerator I5 is dispensed with and with carburetted water gas, the valve 31' is used or omitted as previously described. The valve 46' is used and secondary combustion of blow gases effected in the carburetter II as before and completed in 49 by air admitted through 48. y

The set is air blasted as before and during the running period the steam and any air admixed therewith as desired is superheated in the superheater I2 and passes thence to the lower portion of the generator through 68, 61, 26 at level 24 and is also admitted for carbonization as previously described at level 24h. The up run gases are passed through the carbonizing or is varied as follows: steam is passed downwardly through the newly charged fuel in chamber 2|, Fig. l, or in chamber 80 in Fig. 2- the steamI being admitted above the fuel as at 24d in Fig. l. This steam is preferably superheated and supplied to 24d from either 42 or 6B with the valve 31 or'46 closed meanwhile. The assembly 33 may be modified or dispensed with as desired. 'I'he steam and distillation gases then pass..down Wardly through the incandescent fuel in the generator and the hydrocarbon gases are cracked .previously described. In this case when a maximum production of hydrogen is desired preferably the down run steam only is passed through the-newlycharged fuel so all the hydrocarbon gases and vapors therefrom maybe substantially reduced to carbon and hydrogen.

- The hydrogen content of the gases may also be increased by spraying in liquid hydrocarbons over the fire as at 24c admixed with steam when desired and preferably into a vcurrent of highly superheated steam entering the generator through 31. The liquid hydrocarbon is then cracked into hydrogen and carbon with the carbon therefrom in contact with the steam at.

high temperatures forming water gas mostly. 'Ihese down run gases 4are drawn oif from the lower part of the generator as previously described. p

In Fig. 3 is shown a modified method for drawing off liquid slag from the base of the generator. The slag level in the spout at 86 is sufficiently higher than in the generator at l85 to seal off the gases at the higher pressurev in the generator. As the slag accumulates in the generator the slag overflows at 86. A heating means for keeping the slag liquid in the spout. is indifcated by a gas burner 8l. At 88 is shown a plug which may be removed for draining out the slag as in shutting down.

In Fig. 4 is shown'another method for drawing off liquid metal at opening lilv and slag at 92. separately as for example when iron ore. or othermetal-containing4 material is used as aux, the molten metal being indicated by 9|) and the liquid slag at 85.

The pipe 93 in. Fig. f4 may be used for admitting a fluxing material in the air tuyres which may be blown in with the blasting Also gas or oxygen may be admitted through '93 and mixed with the blasting air as previously describedi In'cracking methane and/or natural or other hydrocarbon gases, the air blasting is carried on as described, and said4 gases. admixed with steam when desired, are passed through the re-- 'generators and incandescent fuel bed in the same manner as described for steam. The thick high temperature fuel bed cracks the gas into hydrogen and carbon mostly, with the hydrogen gas and any water gas formed therewith drawn olf as previously described for water gas.

From the preceding description it will be seen that the invention provides highly .eilcient methods for removing ash and clinker forming material as liquid slag with up runs only, down runs only, or combination up and down runs with the sensible heat of the blue 'gas and/or carburetted water gas and sensible and potential heat in the blow gas utilized in superheat- W The hydrogen and waterv gas then 1. The herein described improvement in the Vmethod of manufacturing water gas which includes: air blasting a generator fuel bed to lncandescence by air-admitted in the lower portion thereof; alternately with the air blasting, admitting steam and a restricted amount of air simultaneouslyand admixed to the fuel column in the lower portion thereof above the air'blast steam to the upper portion ofv the fuel column for a 'down 11m; drawing off the up rungases from theupper portion of...the fuel..colum'n; drawing oi the gas from the lower portion of the column; admitting air to the lower portion of the fuel bed during the up run of steam and in an amount restricted such that the heat liberated by the combustion thereof is less than the heat absorbed in the decomposition of the up run steam, and discharging ash and clinkerforming material as liquid slag.

2. The herein described improvement in the method of manufacturing water' gas which includes: air blasting to incandescence, the lower portion of a generatorfuel bed having an upper newly charged fuel portion; passing the blow gases thereby produced from the .upper portion of said incandescent portion of the fuel bed; alternately with the air blasting, admitting steam to the fuel column in the lower portion thereof above the air blast level and causing the gas thereby produced to pass from the upper portion of said incandescent portion of the fuel bed throughsaid newly charged fuel portion and, alternately of said steam admission, admitting steam to the upper portion of the incandescent portion of the fuel column, passing the same downwardly and drawing off the gas thereby produced from the lower portion of the column; and discharging ash and clinker-forming material as liquid slag.

3. The .herein described improvement in the manufacture of water gas which includes: air blasting a column of fuel to inoandescence in the lower portion thereof; alternately with the air blasting, admitting steam to vthe fuel column alternately in the lower portion thereof above the air blast level and drawing off the gas thereby produced from the upper portion of the fuel column, and to the upper portion of the fuel column; drawing oi the gas thereby produced from the lower portion of the column and causing said gas to pass through a regeneratorfor l steam admitted to the lower portion of the fuel column in said vgenerator and discharging ash and clinker-forming material as liquid slag.

4. The herein described improved in the manufacturel of water gas which includes: air blasting a column of fuel toA incandescence in the lower portion thereof; alternately with the `air blasting, admitting steam to the fuel column alternately in the lower portion thereof above the air blast level and drawing off the gas thereby produced from the upper portion of the fuel column, and to the upper portion of the fuel column; drawing oif the gas thereby produced from the lower portion of the column and causing said gas to pass through a regenerator having upper and lower regenerative zones for heating the same, and generating and superheatlng the steam admitted to the lower portion of said generative fuel bed by admitting and superheating steam in said lower regenerative zone, admitting water thereaLbove and vaporizing such water in the column of superheated steam rising alternately with the air blasting, generating water gas by admitting steam to the fuel column successively in thelower portion thereof above the slagging bottom and air blast level for an up run and then in the upper portion for a. down run; withdrawing the formed water gas from the `up run from 'the upper portion of thefuel column and the formed water gas from the downr run from the lower portion of the incandescent fuel; and discharging ash and clinkereformlng l0 material as liquid slag.

HIRAM J. CARSON. 

